FABRICATION OF ULTRATHIN SILICON DIOXIDE LAYERS IN ROOM-TEMPERATURE BY ULTRAHIGH-VACUUM PLASMA OXIDATION

Plasma oxidation of silicon in room temperature and in an ultrahigh va cuum has been found to be a useful tool in producing very thin silicon dioxide layers. The maximum thickness that can be reached, however, i s only 1-1.1 nm. As the needed layer thickness is usually from 2 to 5 nm, the process has to be performed in several oxidation cycles. Using this method, a good thickness control can be achieved and the resulti ng MOS structures have relatively low surface state densities and a hi gh breakdown field. (C) 1998 Elsevier Science B.V. All rights reserved .